1. Field of the Invention
The present invention relates to a data communication system, an information processing apparatus, an information processing method, and a program, and more particularly to a data communication system, an information processing apparatus, an information processing method, and a program that can provide images of reliable quality over a network.
2. Description of Related Art
As an adaptive rate control method for use in data transmission/reception using RTP (Real Time Transport Protocol)/RTCP (RTP Control Protocol), a method is proposed that allows an apparatus of a data receiving side to estimate the data transmission status at an apparatus of a data transmitting side and to control the transmission rate based on information described in an RR (Receiver Report) packet of the RTCP that notifies to the apparatus of the data transmitting side information on a packet loss rate, jitters, and so on. For example, it is described in Japanese Laid-Open Patent JP2002-204278A.
Another proposed method is that the apparatus of the data transmitting side detects a network congestion based on an arrival delay of a packet, and controls the data transmission rate based on the detection result. For example, it is described in Japanese Laid-Open Patent JPH11-308271.
A still another proposed method is that an optimum data transmission rate is being sought by increasing or decreasing the data transmission rate of the transmitting side. For example, it is described in Japanese Laid-Open Patent JPH11-341064.
Like the method disclosed in the published JPH11-308271, this method basically uses a SR (Sender Report) packet and an RR packet of the RTCP to allow the transmitting side to detect a transmission delay of a packet (RTT based delay) based on information from the receiving side for controlling the transmission rate.
A still another technology is that the data receiving side estimates the transmission band of a network and, based on the estimation, the data receiving side transmits a transmission control instruction to the data transmitting side for controlling the data transmission rate. For example, it is described in Japanese Laid-Open Patent JP2000-115245.